ExtensionSubtables.cpp

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/*
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 * (C) Copyright IBM Corp. 2002 - All Rights Reserved
 *
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#include "LETypes.h"
#include "OpenTypeTables.h"
#include "GlyphSubstitutionTables.h"
#include "LookupProcessor.h"
#include "ExtensionSubtables.h"
#include "GlyphIterator.h"
#include "LESwaps.h"

U_NAMESPACE_BEGIN

// read a 32-bit value that might only be 16-bit-aligned in memory
#define READ_LONG(code) (le_uint32)((SWAPW(*(le_uint16*)&code) << 16) + SWAPW(*(((le_uint16*)&code) + 1)))

// FIXME: should look at the format too... maybe have a sub-class for it?
le_uint32 ExtensionSubtable::process(const LEReferenceTo<ExtensionSubtable> &thisRef,
                                     const LookupProcessor *lookupProcessor, le_uint16 lookupType,
                                      GlyphIterator *glyphIterator, const LEFontInstance *fontInstance, LEErrorCode& success) const
{

    if (LE_FAILURE(success)) {
        return 0;
    }

    le_uint16 elt = SWAPW(extensionLookupType);

    if (elt != lookupType) {
        le_uint32 extOffset = READ_LONG(extensionOffset);
        LEReferenceTo<LookupSubtable> subtable(thisRef, success,  extOffset);

        if(LE_SUCCESS(success)) {
          return lookupProcessor->applySubtable(subtable, elt, glyphIterator, fontInstance, success);
        }
    }

    return 0;
}

U_NAMESPACE_END